JPH032796B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Description of the technical field The present invention relates to an improvement of a swing control device for a cable crane.

(b) Description of Prior Art Figure 1 is for showing the configuration of a swinging cable crane. The swinging cable crane is
A rope 3 and a winch 4 for swinging the swinging post 1 to the right toward the plane of the paper around the swinging post base 2, and a rope 5 and a winch for swinging the swinging post 1 to the left. 6. It is composed of a trolley 9, a hoisting rope 10, and a hook 11 suspended from a cable 8 stretched between the upper ends of the swinging column 1 and the fixed column 7. A hanging load 12 is hung on the hook 11, and the swinging column 1 is swung to move left and right toward the plane of the paper, and the trolley 9 moves along the cable 8 to move back and forth toward the plane of the paper. The suspended load 12 is moved.

Conventionally, when swinging the swinging strut 1, the motor of the winch that does not support the swinging strut 1 out of the two winches is operated as a torque motor to apply a constant tension to the rope. This prevented the rope from loosening. However, in the conventional method, since the winch motor is used as a torque motor, there is a problem that it is necessary to select a motor taking stall current into consideration.

(c) Purpose of the Invention The present invention has been made based on the above reasons, and is capable of controlling the rope speed of two winches to prevent the rope from becoming too tight or too loose, and swinging the swinging column.
It is an object of the present invention to provide a swing control device for a cable crane that does not have the above drawbacks.

(d) Summary of the invention The present invention determines the relationship between the rope speeds of two winches, and uses the rope speed of the winch supporting the swinging column to optimally set and control the rope speed of the other winch. The present invention provides a dynamic control device.

(e) Structure and operation of the invention The present invention will be described below with reference to an embodiment shown in the drawings. FIG. 2 shows the configuration of the present invention, in which 13 is a controller that provides a speed reference to the winch, 14 is a winch 4 drive device, 15 is a winch 6 drive device, 16 is a rope speed detector linked to winch 4, and 17 is a winch. 4, a rope length a detector linked to the winch 6, 18 a rope speed detector linked to the winch 6, 19 a rope length b detector linked to the winch 6, 20 a swinger that outputs the length L of the swinging support 1. 21 is a distance setting device that outputs the distance M; 22 is a distance setting device that outputs the distance N; 23 is a contact point 24 where the swinging column 1 is tilted toward the winch 6 side;
Close the contact 25 and open the contact 25, and the swinging strut 1
This is a tilt direction detector that opens a contact 24 and closes a contact 25 when the vehicle is tilted to the side.

Further, 26 is the output Va of the rope speed detector 16,
Output a of rope length a detector 17, output b of rope length b detector 19, output L of swinging strut length setting device 20, output M of distance setting device 21, and distance setting device 22
From the output N of the winch 6, the rope speed reference is
This is a computing unit that outputs Vbr. 27 are the output Vb of the rope speed detector 18, the output b of the rope length b detector 19, the output a of the rope length a detector 17, the output L of the swing strut length setting device 20, and the output M of the distance setting device 21. , the output N of the distance setting device 22, and outputs the rope speed reference Var of the winch 4.

FIG. 3 is a diagram showing the mechanical specifications used in FIG. 2, including the length L of the swinging strut 1, the rope lengths a from the upper end of the swinging strut 1 to winch 4 and winch 6, and b, distances N and M from the swinging strut base 2 to the winch 4 and winch 6, the angle θ between the swinging strut 1 and the straight line connecting the swinging strut base 2 and the winch 4, the swinging strut base 2 and the winch 4 and the angle φ formed by the straight line connecting the swing column base 2 and the winch 6.

In the figure, if θ is an arbitrary function of time t, θ=f(t) (1), the rope lengths a and b are given by the following equations.

a=√ ² + ² −2()…(2) b=√ ² + ² −2{−()}…(
3) Here, from equations (2) and (3), the time rate of change of a and b,
In other words, the rope speeds Va and Vb are Also, from equations (4) and (5), Vb=-a/b・M/N・sin {φ-f(t)}/sinf
(t)・Va…(6) Va=−b/aN/M・sinf(t)/sin{φ−f(t
)}・Vb...(7) Here, the negative signs in equations (6) and (7) indicate that one of Va and Vb indicates the speed in the feeding direction, and the other indicates the speed in the winding direction. In the above, this sign is ignored and Va and Vb are treated as positive values. Here, equation (2), (3)
From the formula, cosf(t)=L ² +N ² −a ² /2LN …(8) cos {φ−f(t)}=L ² +M ² −b ² /2LM …(9) Considering the following, winch 6 Rope speed reference Vbr
From equation (6), The rope speed standard Var of winch 4 is obtained from formula (7). becomes.

Therefore, when the swing column 1 is tilted toward the winch 6, the tilt direction detector 23 detects the contact point 24.
Since the contact 25 is closed and the contact 25 is open, the winch 4 is operated at the rope speed Va corresponding to the notch of the controller 13. And the speed standard corresponding to this Va
Vbr is output from the calculator 26 according to equation (10), and the winch 6 is controlled. If the opposite swinging column 1 is tilted toward the winch 4 side, the tilt direction detector 2
3, contact 24 is open and contact 25 is closed, so
The winch 6 is operated at a rope speed Vb corresponding to the notch of the controller 13. And this Vb
The speed reference Var corresponding to
7, and the winch is controlled.

(f) Other Examples The configuration of the swinging part shown in Figure 3 is a general case in which each machine specification is arbitrarily determined, and the structure of the swinging part of a cable crane that is commonly used. In most cases, the following special conditions are attached in FIG. 2: M=N...(12) φ=π(rad)...(13) In this case, equations (12), (13) to (6), and (7)
The formula is Vb=-a/bVa (14) Va=-b/aVb...(15) The function of the present invention can be achieved by very simple calculations by the calculators 26 and 27 in FIG. This can be easily achieved.

(g) Overall effect As explained above, according to the present invention, when swinging the swinging column of a cable crane, the rope speed of the two winches is adjusted to prevent the rope from becoming too tight or too loose. An effective cable crane swing control device that can control the swing of the swing strut 1 can be provided.

[Brief explanation of the drawing]

FIG. 1 is an overall configuration diagram of an oscillating cable crane, FIG. 2 is a block diagram showing an embodiment of the present invention, and FIG. 3 is a relationship diagram of mechanical specifications used in FIG. 2. 1... Swing column, 2... Swing column base, 3, 5...
...Rope, 4,6...Winch, 7...Fixed support, 8...Cable, 9...Trolley, 10...
hoisting rope, 11... hook, 13... controller, 14, 15... winch drive device, 16,
18... Rope speed detection device, 17, 19... Rope length detection device, 20... Swing strut length setting device, 2
1, 22...Distance setter, 23...Inclination direction detector, 26, 27...Arithmetic unit.

Claims (1)

[Claims] 1 A cable is stretched between a fixed support and a swinging support, and a pair of winches are connected via a rope extending from a connection point between the swing support and the cable, and the connection point of the rope is connected to a pair of winches. and a rope length detector for detecting each of the rope lengths of the rope; and a rope length detector for detecting each of the rope lengths of the rope; a rope movement speed detector that detects the moving speed of the rope controlled by the rope; a slope direction detector that detects the inclination direction of the swinging support; and a rope movement speed detector that detects the moving speed of the rope controlled by the swing support; a length setting device to set, a distance setting device between the swing column base and each of the winches, and the rope length detector/
Control by each of the winches to prevent the rope from becoming too tight or too loose based on each output from the rope moving speed detector, the inclination direction detector, the length setting device, and the distance setting device using a predetermined relational expression. A swing control device for a cable crane, comprising a computing unit that computes a reference speed of movement of each rope.